title: Analysis of the Aspergillus fumigatus proteome reveals metabolic changes and the activation of the pseurotin A biosynthesis gene cluster in response to hypoxia.
abstract: The mold Aspergillus fumigatus is the most important airborne fungal pathogen. Adaptation to hypoxia represents an important virulence attribute for A. fumigatus. Therefore, we aimed at obtaining a comprehensive overview about this process on the proteome level. To ensure highly reproducible growth conditions, an oxygen-controlled, glucose-limited chemostat cultivation was established. Two-dimensional gel electrophoresis analysis of mycelial and mitochondrial proteins as well as two-dimensional Blue Native/SDS-gel separation of mitochondrial membrane proteins led to the identification of 117 proteins with an altered abundance under hypoxic in comparison to normoxic conditions. Hypoxia induced an increased activity of glycolysis, the TCA-cycle, respiration, and amino acid metabolism. Consistently, the cellular contents in heme, iron, copper, and zinc increased. Furthermore, hypoxia induced biosynthesis of the secondary metabolite pseurotin A as demonstrated at proteomic, transcriptional, and metabolite levels. The observed and so far not reported stimulation of the biosynthesis of a secondary metabolite by oxygen depletion may also affect the survival of A. fumigatus in hypoxic niches of the human host. Among the proteins so far not implicated in hypoxia adaptation, an NO-detoxifying flavohemoprotein was one of the most highly up-regulated proteins which indicates a link between hypoxia and the generation of nitrosative stress in A. fumigatus.
authors.affiliation: Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology-Hans-Knöll-Institute and Friedrich Schiller University, Jena, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Vödisch
authors.forename: Kirstin
authors.initials: K
authors.lastname: Scherlach
authors.forename: Robert
authors.initials: R
authors.lastname: Winkler
authors.forename: Christian
authors.initials: C
authors.lastname: Hertweck
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Braun
authors.forename: Martin
authors.initials: M
authors.lastname: Roth
authors.forename: Hubertus
authors.initials: H
authors.lastname: Haas
authors.forename: Ernst R
authors.initials: ER
authors.lastname: Werner
authors.forename: Axel A
authors.initials: AA
authors.lastname: Brakhage
authors.forename: Olaf
authors.initials: O
authors.lastname: Kniemeyer
mesh_terms: D000693:Anaerobiosis / Q000235:genetics* / Q000502:physiology; D001232:Aspergillus fumigatus / Q000378:metabolism*; D015152:Blotting, Northern; D002851:Chromatography, High Pressure Liquid; D017931:DNA Primers / Q000235:genetics; D015180:Electrophoresis, Gel, Two-Dimensional; D004591:Electrophoresis, Polyacrylamide Gel; D015966:Gene Expression Regulation, Fungal / Q000235:genetics* / Q000502:physiology; D013058:Mass Spectrometry; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D015394:Molecular Structure; D010101:Oxygen Consumption / Q000502:physiology; D020543:Proteome / Q000378:metabolism*; D040901:Proteomics / Q000379:methods*; D011760:Pyrrolidinones / Q000737:chemistry / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D017931:DNA Primers; D020543:Proteome; D011760:Pyrrolidinones; C012013:pseurotin